In the operation of airbrushes, the airbrush itself is hand held and the artist creates the color on the intended surface by hand and arm movements while triggering the airbrush mechanism to control the flow of paint being applied to the surface. It is tedious and exacting work. The artist is physically unable to reproduce the work exactly or to produce the work on any kind of assembly line fashion. In spite of even the best human eye-hand-arm coordination, the airbrush artist is left to a single or one-at-a-time produce, no two of which can be called reproductions of the original or first product. Creation of an airbrush painting is time consuming because of the frequent need to stop and clean the airbrush between each color change and the relatively slow arm and hand movements desired for exacting work, such as that required to tint a photograph. It is also tiring work because the airbrush is relatively heavy.
Airbrush painting utilizes compressed air from a nozzle to atomize paint. The nozzle operates by impinging turbulent air on or across a surface containing paint causing the paint to collapse into droplets which are then directed onto a surface. The general configuration of the airbrush includes a source of fluid, e.g. paint, which is connected to a control or needle valve. As air passes over the needle valve it creates a vacuum which draws fluid from a remote source out of the valve into the airstream where the fluid or paint is sprayed or projected onto a surface of paper or other material. As used herein, the term "paint" is intended to include color, pigment, paint or other colorants and fluids for creating images on a surface.
Frequently, the source of paint for use in airbrush painting is mounted on the airbrush itself by way of a screwed jar or container or similar source reservoir. This configuration creates space problems and adds weight to the airbrush, thereby making it all the more difficult for the human artist to perform exacting artwork for any extended period of time. Also, such configuration is messy an awkward when the jar or container must be changed for each change of color.
These and other shortcomings in airbrush painting are largely overcome by the present invention which combines airbrush technology with robotics.
There has been increased use of automated painting and coating apparatus such as in assembly lines in automobile plants or for coating a series of objects to be painted or otherwise coated as the objects pass a spray station. Some of these assembly lines have used computers for programming color changes during the assembly line operation and some use industrial robots to manipulate the painting process in a spray booth.
Broadly, industrial robots perform such tasks as welding, machine loading and unloading, material handling, spray finishing, assembly and machinery applications. The majority of industrial robots are not "smart" or "intelligent" manipulators largely because their ability to sense objects in their environment is still not perfected. In all practical applications, robots, for the most part, are deficient in vision and touch.
These and other deficiencies have heretofore made robotics unacceptable for detailed painting and artwork utilizing the exacting apparatus of an airbrush.